1. Field of the Invention
The present invention relates generally to equipment for folding fabric, in continuous webs or tubes, and more particularly to a high speed fabric folder suitable intr alia for knitted textiles.
2. Background of the Invention
After being knitted and processed, a knitted fabric usually is batched either in roll form or folded for delivery to be cut and sewn to make garment. With more cutting and sewing being done remote from knitting mills, delivery of knitted fabrics in folded form is increasing in popularity. Large folded bundles typically are shipped in containers to be cut and sewn into garments. In order to transport the large bundles efficiently without distortion a folded pile is required to be neat and accurate in size. Speed at which a fold is made also is an important economic concern. According to the prior art, in order to provide a neat folded pile, machines had to be slowed down; especially when traversing type folders are used. Reciprocating motion involving change in direction of traversing rolls create extreme impact forces. In addition a requirement to pat down or press an end of each fold with flaps or other means adds to impact stress imposed on the folding mechanism. Many attempts have been made to reduce the impact stress without adversely affecting quality of folding.
One such attempt is described in U.S. Pat. No. 4,175,738. In the ""738 folder there is an attempt to reduce the impact stress resulting from change in direction of a traversing roll by slowing down the roll at the end of its stroke. This ""738 folder requires a relatively complex mechanical assembly including a yoke and slide mechanism and a relatively complex gear assembly.
Despite achievements of prior art folders there remains a need for a simple and effective folder, particularly for knitted fabrics, which can operate satisfactorily at an acceptly rapid rate of speed within acceptable impact stress levels.
It is an object of the present invention to use impact stress caused by the pressing assembly in a high speed folder to reduce the impact stress caused by the traversing assembly to an acceptable level.
Another object of the present invention is to provide a high speed fabric folder which incorporates a shock absorbing means to reduce shock imposed by impact stress on the folder""s traversing assembly.
Another object of the present invention is to provide a high speed fabric folder which incorporates a traveling roll to press the pile of folded fabric.
Another object of the present invention is to provide a high speed fabric folder which operates in a safe and reliable manner within acceptable impact stress levels.
Another object of the present invention is to provide a high speed fabric folder which reduces impact stress on the folding mechanism without adversely affecting the quality of folding or speed of operation.
Another object of the present invention is to provide a high speed fabric folder which produces a uniform length of fold and a neat folded pile.
Yet another object of the present invention is to provide a high speed fabric folder which comprises a relatively small number of component parts and which can be manufactured economically resulting in a relatively low overall cost.
The foregoing and other objects and features of the invention will appear more clearly hereinafter.
In accordance with the present invention, there is provided a high speed fabric folder which includes a traversing assembly mounted on a base. The traversing assembly includes fabric conduit means which receive a fabric web and deposit the fabric in a Z fold or fan fold as the traversing assembly reciprocates relative to the base.
A pressing assembly which includes a pair of pressing rollers is mounted on the traversing assembly. The pressing roller moves in a direction that is substantially parallel to the surface of the folded pile of fabric and presses lightly on the pile of fabric as it moves toward the fold.
Shock absorber assemblies absorb impact stress at the ends of strokes of the traversing assembly as it reciprocates relative to the base.